public override async Task <ResponseMessage> SendAsync(
RequestMessage request,
CancellationToken cancellationToken)
{
try
{
ResponseMessage response = await this.ProcessMessageAsync(request, cancellationToken);
Debug.Assert(System.Diagnostics.Trace.CorrelationManager.ActivityId != Guid.Empty, "Trace activity id is missing");
return(response);
}
//catch DocumentClientException and exceptions that inherit it. Other exception types happen before a backend request
catch (DocumentClientException ex)
{
Debug.Assert(System.Diagnostics.Trace.CorrelationManager.ActivityId != Guid.Empty, "Trace activity id is missing");
return(ex.ToCosmosResponseMessage(request));
}
catch (CosmosException ce)
{
Debug.Assert(System.Diagnostics.Trace.CorrelationManager.ActivityId != Guid.Empty, "Trace activity id is missing");
return(ce.ToCosmosResponseMessage(request));
}
catch (OperationCanceledException ex)
{
// Catch Operation Cancelled Exception and convert to Timeout 408 if the user did not cancel it.
// Throw the exception if the user cancelled.
if (cancellationToken.IsCancellationRequested)
{
throw;
}
Debug.Assert(System.Diagnostics.Trace.CorrelationManager.ActivityId != Guid.Empty, "Trace activity id is missing");
CosmosException cosmosException = CosmosExceptionFactory.CreateRequestTimeoutException(
message: ex.Data?["Message"].ToString(),
headers: new Headers()
{
ActivityId = System.Diagnostics.Trace.CorrelationManager.ActivityId.ToString()
},
innerException: ex,
trace: request.Trace);
return(cosmosException.ToCosmosResponseMessage(request));
}
catch (AggregateException ex)
{
Debug.Assert(System.Diagnostics.Trace.CorrelationManager.ActivityId != Guid.Empty, "Trace activity id is missing");
// TODO: because the SDK underneath this path uses ContinueWith or task.Result we need to catch AggregateExceptions here
// in order to ensure that underlying DocumentClientExceptions get propagated up correctly. Once all ContinueWith and .Result
// is removed this catch can be safely removed.
ResponseMessage errorMessage = AggregateExceptionConverter(ex, request);
if (errorMessage != null)
{
return(errorMessage);
}
throw;
}
}
internal static ResponseMessage AggregateExceptionConverter(AggregateException aggregateException, RequestMessage request)
{
AggregateException innerExceptions = aggregateException.Flatten();
DocumentClientException docClientException = (DocumentClientException)innerExceptions.InnerExceptions.FirstOrDefault(innerEx => innerEx is DocumentClientException);
if (docClientException != null)
{
return(docClientException.ToCosmosResponseMessage(request));
}
Exception exception = innerExceptions.InnerExceptions.FirstOrDefault(innerEx => innerEx is CosmosException);
CosmosException cosmosException = exception as CosmosException;
if (cosmosException != null)
{
return(cosmosException.ToCosmosResponseMessage(request));
}
return(null);
}